Year Percent change (Units) 1999 24.752 2000 -4.341 2001 -6.569 2002 -7.797 2003 81.787 2004 53.386 2005 1.675 2006 5.638 2007 1.889 2008 8.228 2009 3.379 2010 6.403 2011 7.546 2012 13.936 2013 7.628 2014 0.738 2015 2.537 2016 15.199 2017 -3.399 2018 4.703 2019 5.368 2020 -12.055 2021 1.580 2022 6.983 2023 -2.176 2024 1.377 2025 5.312 2026 3.766 2027 3.551 2028 3.556 2029 3.557